“Jehoiada” means Jehovah knows

1. Father of Benaiah, David's well-known warrior. (2 Samuel 8:18) 1Kin 1 and 2 passim ; (1 Chronicles 18:17) etc. (B.C. before 1046.)
2. Leader of the Aaronites, i.e. the priests; who joined David at Hebron. (1 Chronicles 12:27) (B.C. 1053-46.)
3. According to (1 Chronicles 27:34) son of Benaiah; but in all probability Benaiah the sons of Jehoiada is meant. Probably an error in copying. (1 Chronicles 18:17; 2 Samuel 8:18)
4. High priest at the time of Athaliah's usurpation of the throne of Judah, B.C. 884-878, and during the greater portion of the forty-years reign of Joash. He married Jehosheba; and when Athaliah slew all the seed royal to Judah after Ahaziah had been put to death by Jehu, he and his wife stole Joash from among the king's sons and hid him for six years in the temple, and eventually replaced him on the throne of his ancestors. [ATHALIAH] The destruction of Baal-worship and the restoration of the temple were among the great works effected by Jehoiada. He died B.C. 834.
5. Second priest, or sagan, to Seraiah the high priest. (Jeremiah 29:25-29; 2 Kings 25:18)
6. Son of Paseach, who assisted to repair the old gate of Jerusalem. (Nehemiah 3:6)